The Influence of Aggregate Gradation on the Permeability and Mechanical Properties of Porous Concrete

The influence of aggregate gradation on the permeability and mechanical properties of porous concrete was investigated. A standard mix and five standard aggregate gradations were selected. Since porous concrete contains no or little fine aggregate, its structure is formed by the interlocking of the coarse aggregates. So the aggregate gradation is a very important characteristic as it influences such properties of porous concrete as strength and permeability. There was statistically significant difference between the results from the strength and water permeability of porous concrete with different aggregate gradations. For example, the difference between minimum and maximum compressive strength was 33%, and a 20% difference was obtained for flexural strength. It was found that the uniformity coefficient has influence on the flexural strength of porous concrete. In order to develop the flexural bending strength prediction model, the two parameters of compressive and uniformity coefficient were explained using linear regression model. The obtained Goodness of fit (R2) for this model was 0.879. The results of the current investigation showed how fine aggregate influenced the compressive and permeability of porous concrete.